Washington State University

About: Washington State University is a education organization based out in Pullman, Washington, United States. It is known for research contribution in the topics: Population & Gene. The organization has 26947 authors who have published 57736 publications receiving 2341509 citations. The organization is also known as: WSU & Wazzu.

Berry Temperature and Solar Radiation Alter Acylation, Proportion, and Concentration of Anthocyanin in Merlot Grapes

Abstract: Using a forced convection system, temperatures of Merlot grape clusters were monitored and controlled between veraison and harvest to produce a dynamic range of berry temperatures under field conditions in both sun-exposed and shaded fruit. Ten combinations of temperature and solar radiation exposure were used to quantify effects on phenolic profiles (anthocyanins and flavonol-glycosides) and on total concentrations of skin anthocyanin (TSA) in the fruit at commercial maturity. Exposure of berries to high temperature extremes for relatively short periods during ripening appears to alter the partitioning of anthocyanins between acylated and nonacylated forms and between dihydroxylated and trihydroxylated branches of the anthocyanin biosynthetic pathway. Specifically, among flavonol-glycosides, quercetin 3-glucoside increased with exposure to solar radiation. Low incident solar radiation alone appeared not to compromise total anthocyanin accumulation; rather, a combination of low light and high berry temperatures decreased TSA. Regardless of exposure to solar radiation, higher berry temperatures led to a higher concentration and a higher proportion of TSA comprised by malvidin-based anthocyanins, driven primarily by increases in the acylated derivatives. Under shade alone and under high temperature extremes in sunlit and shaded fruit, acylated anthocyanins represented a larger proportion of TSA than did nonacylated anthocyanins. At berry temperatures equivalent to those of shaded fruit, exposure to solar radiation decreased the proportion of TSA comprised by acylated forms of the five base anthocyanins and increased the proportion of TSA comprised by dihydroxylated anthocyanins. Results indicate a complex combined effect of solar radiation and berry temperature on anthocyanin composition, synergistic at moderate berry temperatures and potentially antagonistic at high temperature extremes.

Exploratory and confirmatory tests of the big five and Tellegen's three- and four-dimensional models.

Abstract: Using about 600 college students and exploratory and confirmatory factor analysis, three models of personality structure were tested: the Big Five, as measured by the NEO Personality Inventory (P.T. Costa & R. R. McCrae, 1985), and A. Tellegen's (1985) three- and four-dimensional models, as measured by the Multidimensional Personality Questionnaire (A. Tellegen, 1982). Both factor methods indicated considerable support for, but also some divergences from, the models. We concluded that parsimonious personality models are unlikely to meet conventional goodness-of-fit criteria in confirmatory factor analysis, because of the limited simple structure of personality measures and the personality domain itself. Poor fits of a priori models highlighted not only the limited specificity of personality structure theory, but also the limitations of confirmatory factor analysis for testing personality structure models.

Protein immobilization on carbon nanotubes via a two-step process of diimide-activated amidation

Abstract: Ferritin and bovine serum albumin (BSA) proteins are chemically bonded to nitrogen-doped multi-walled carbon nanotubes (CNx MWNTs) through a two-step process of diimide-activated amidation. First, carboxylated CNx MWNTs were activated by N-ethyl-N′-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDAC), forming a stable active ester in the presence of N-hydroxysuccinimide (NHS). Second, the active ester was reacted with the amine groups on the proteins of ferritin or BSA, forming an amide bond between the CNx MWNTs and proteins. This two-step process avoids the intermolecular conjugation of proteins, and guarantees the uniform attachment of proteins on carbon nanotubes. TEM and AFM measurements clearly confirmed the successful attachment. This approach provides a universal and efficient method to attach biomolecules to carbon nanotubes at ambient conditions.